Power tranemission



POWER TRANSMI S S ION Filed Nov. 14, 1927 5 Sheets-Sheet 1 FIG. I

FIBLBI INVENTOR (LL/2.01M

Dec. 25, 1928.

L. R. BUSHYAGER POWER TRANSMI S S ION Filed Nov. 14, 1927 5 Sheets-Sheet 2 04b 0W INVENTOR a 6 W Dec. 25, 1928. 1,696,836

L. R. BUSHYAGER 7 POWER TRANSMI SS ION Filed Nov. 14, 1927 s Sheets-Sheet 5 ruled on. I

' N -TEDiisrATEs' 1,696,836 PATENT OFFICE.

31183 1461301- ucx meme, an army.

1 rowummsxrsszom anumiumaxmnm 14, 16:1. Serial :6. 236,124.

My invention to improvements in wer transmission, and consists in them;- sembly with a driven shaft of two prime movers so connected to the driven shaft that, being equal in wer, they may exert equal and counterba anced torques, or, alternatively, either alone may exert its dr vingitorquef, upon the driven shaft. The. 1nvention includes the further provision that when one prime moveralone is active, disconnectionof the otheris automatically assured. a I

In Fig. I of the accompanying drawmgs an assemblyis diagrammatically shown n horizontal plan of a 'drivensha t, which 1n this case is shown to be the propeller shaft of an aeroplane, having associated w1th 1t two prime movers, in this case 'lnternal combustion engines, connected w1th -1t 1n the assembly which constitutes my nvention. Fi II is a view to; larger scale, showing mhorizontal and axial sect onthe caring whose position in the assembly is indicated in Fig. I. Fig. III is a hantom view of the gear case in end e evatlon. Fig. IV is a view corresponding to Fig. II and illustrating an alternative arrangement. Referring first to Fig. I, the propeller shaft of an aeroplane is indicated at 13, and borne by the shaft the blades 14 of the propeller 'are fragmentarily ind cated. Associated with and symmetrically arranged with respect to the shaft 13 are two internal combustion engines, indicated to be identical, whose shafts 1 and 2 enter the gear case 21; on either side of and at roperly remote and in this instance equal distances from the axis of shaft 13.

Referring to Fig. II, the two shafts 1 and 2 are seen to carry integrally within gear case 21 the pinions3 and 4.

The shaft 13 carries integrally a toothed wheel 12, and it carries rotatably a sleeve 7 4 and a cylindrical gear casing 9. The sleeve- 5 7 extends through one head of the gear casing 9, so that e sleeve affords externall a cylindrical bearing surface upon whic the gear casing is through one head rotatably mounted. The sleeve 7 externally of gear casing 9 carries integrally a spur wheel 5, and the gear casing 9 carries integrally a spur wheel 6. The two spur wheels 5 and 6 are in their toothed peripheries identical. With one of them the pinion 3 .is in mesh, with the other the pinion 4.

The gear casing 9 carries rotatably 'gear wheels; one of these, the gear wheel 10, meshes with a inion 8 formed on sleeve .7, and'the other, t 0 gear wheel 11, meshes with toothed wheel 12. The intermeshed gear wheels 8 and 10 are e mil in diameter;

of the intermeshed gear ,w eels 11 and 12, the diameter of 11 is halfthat of 12. Manifestly the number of sets of planetary gears 10, 11 within gear case 9 may be increased indefinitel hey will however advantageously arranged in diametrically opposite pairs. Fig. III indicates an adequate arrangement of two sets arranged in diamettrical opposition.

Within the gear case 21 and adjacent its op osite heads the rotary parts carry two col ars 15 and 16. The collar 15 is borne upon the hub 17 of gearcase 9that is to say, of spur wheel' 6. borne upon the hub 18 of spur wheel 5. The engagement of the two collars 15 and 16 upon the hubs-is by oppositely turned screw threads, and the screw-thread engagement is a loose one. The casing 21 carries, opposite the two collars, brake rings 24. The col- 4 lars 15 and 16 have a narrow range of axial movement to and from binding contact upon brake rings 24.

When either engine is operated alone and the shaft 1 (2) turns in the direction indicated by an arrow, Fig. II, the spur wheel 5 (6) is positively driven, and, because of the engagement of spur wheel 8 with gear wheel 10, the immediate effect is to cause the spur wheel 6 (5) to rotate in opposite direction. Such rotation of the two spur wheels causes the collars 15 and 16, because of inertia, to move by their screw-thread engagement, relatively to the hubs on which they are borne: one collar (16) movee away from, the other (15) to engagement with its brake ring 24- So engaging brake ring 24, the collar 15 (16) looks the spur wheel 6 (5) against continued rotation, and

thereafter the continued rotation of spur wheel 5 (6) is effective to drive shaft 13.

Rotation of spur wheel 5 effects rotation of spur wheel 8 with which it is integrated, and, gear case 9 being locked against turning, rotation of spur wheel 8 turns gear wheels 10 and 11 and so drives spur wheel 12, and with it shaft 13; rotation of spur wheel 6 effects rotation of gear case 9, and,

The collar 16 is spur wheel 8 being locked against turning, rotation of the gear case causes the contained planetary gearm stationary s ur w eel 8 and with the rotatable spur w eel 12, to rotate spur wheel 12, and with it shaft 13.

When both engines are in operation, so long as the shaft speeds are equal, neither can lock the collar 15, 16 of the other, and the torques of both shafts 1 and 2 are transmitted to shaft 13. Any inequality of speed, as between the shafts 1 and 2, expresses itself in a tendency to shift the load to the more rapidly turning shaft, and so to main-t tain equalization.

If, as has been noted of the apparatus shown, the planetary gear be so proportioned as to give a speed ratio as between either driving member 5 and 6 and the driven shaft, of 2: 1, and if the pinions 3 and 4 be-of half the diameter of spur wheels 5 and 6, then with either engine operating alone (the other being-stationary) the speed ratio of engineshaft to propeller shaft will be 4: 1, but if both engines be operating together, the speed ratio of engine shaft to propeller shaft will be 2: 1. If, for example, the engine shaft be turning at 2800 R.

M., if oneengine be operating alone, the propeller shaft will turn at 700 R. P. M. But if both engines be" in operation, the propeller shaft will turn at 1400 R. P. M.

Referring to Fig. IV which, in manner corresponding to Fig. II, illustrates another specific application of the invention in its broader aspects, there are incidental differences to be found, in that a shaft 70, coaxially mounted with and longitudinally aligned with shaft 13, takes the place of the sleeve 7 of Fig. II, and it is the toothed wheels 8 and 10 which in size bear ratio of 1:2, whereas it is the toothed wheels 11 and 12 which are equal in size. The notable difference, however, is that the spur wheels 5 and 6 are individually locked against turning and released, not automatically, but .by means of brake bands 24 and 24, which may be understood to be capable of being tightened and released manually.

With the arrangement of Fig. IV, if one engine alone be in operation and it be desired to bring the other into united operation, the release of the brake band and the sudden throttling of the engine then in operation, will cause the propeller, which will continue to turn under its own momentum,

to act as a starter for the other engine. And hen the second engine has so been started, both may be continued in operation.

A number of advantages are to be gained in mesh both with the in the practice of my invention. First and foremost, for any given engine there is an optimum speed, aspeed at which the en 'ne operates with reatest economy. It has n "a difiicult w ich my invention overcomes,

of so com ining two engines with one shaft that optimum engine speed may be maintained, whether the en 'nes act singly or together in driving the s aft.

The two engine shafts are equidistant on opposite sides of the driven shaft, and the gear ratio is the same for both. When, therefore, the two engines are in simultaneous operation lateral thrusts, being substantiall e ual, are substantially balanced.

Tie s afts all extend in parallelism, the gears all are simple, connections all are direct. This makes for durability, efiiciency, and econom In aerop ane building, the two engines may be containedin one housing, with corresponding saving in resistance to travel.

The regilar, single-engine plane structure may used, with the engines and the propeller mounted in the nose of the fuselage, with economy of space and with minimum resistance to travel.

I claim as my invention:

1. In combination with a driven shaft, two prime movers provided each with a power shaft, a collar threaded upon a member rotating in unison with each power shaft and movable by virtue of such threaded conmotion to and from an oppositely set, fixed abutment, and gearing connectin the two power shafts with the driven sha 2. In power transmitting apparatus a driven shaft bearing integrally a toothed wheel, two spur wheels of equal size rotatable coaxially with said driven shaft, two power shafts each provided with a pinion meshing one with each of the two spur wheels first named, one of the two spur wheels first named bearing integrally a gear case and the other bearing integrally a pinion arranged within the gear case, a planetary gearing member consisting of two gear wheels integrated on a common axle and rotatably borne in said gear case and meshing by means of its two gear wheels with the toothed wheel which is integral with the driven shaft and with the pinion which is integral with the other of the two spur wheels first named, and means for holding each of the spur wheels first named against rotation.

In testimony whereof I have hereunto set my hand.

LEE R. BUSHYAGER. 

